Self‐Assembly of Flexible Free‐Standing 3D Porous MoS2‐Reduced Graphene Oxide Structure for High‐Performance Lithium‐Ion Batteries

• Published in: Advanced functional materials Vol. 27; no. 22
• Main Authors: Chao, Yunfeng, Jalili, Rouhollah, Ge, Yu, Wang, Caiyun, Zheng, Tian, Shu, Kewei, Wallace, Gordon G.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 13-06-2017
• Subjects: 3D porous structure; Anodes; Battery cycles; Crystal structure; Current density; Discharge; Dispersion; Electrochemical analysis; Electrodes; Electronic devices; free‐standing films; Gelation; Graphene; Liquid crystals; Lithium; Lithium-ion batteries; Materials science; Molybdenum disulfide; MoS2–graphene composites; Rechargeable batteries; Self-assembly; Wearable technology
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.201700234

Flexible freestanding electrodes are highly desired to realize wearable/flexible batteries as required for the design and production of flexible electronic devices. Here, the excellent electrochemical performance and inherent flexibility of atomically thin 2D MoS2 along with the self‐assembly properties of liquid crystalline graphene oxide (LCGO) dispersion are exploited to fabricate a porous anode for high‐performance lithium ion batteries. Flexible, free‐standing MoS2–reduced graphene oxide (MG) film with a 3D porous structure is fabricated via a facile spontaneous self‐assembly process and subsequent freeze‐drying. This is the first report of a one‐pot self‐assembly, gelation, and subsequent reduction of MoS2/LCGO composite to form a flexible, high performance electrode for charge storage. The gelation process occurs directly in the mixed dispersion of MoS2 and LCGO nanosheets at a low temperature (70 °C) and normal atmosphere (1 atm). The MG film with 75 wt% of MoS2 exhibits a high reversible capacity of 800 mAh g−1 at a current density of 100 mA g−1. It also demonstrates excellent rate capability, and excellent cycling stability with no capacity drop over 500 charge/discharge cycles at a current density of 400 mA g−1.
A flexible free‐standing porous MoS2–graphene film is fabricated via a facile spontaneous self‐assembly process and subsequent freeze‐drying. The birefringent lyotropic liquid crystalline behavior in the precursor facilitates the hydrogel formation. The produced film exhibits greatly improved electrochemical properties in lithium‐ion batteries. This work may provide a new avenue for the development of flexible composite electrodes.